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Dataplot Vol 2 Vol 1

MATCDF

Name:
    MATCDF (LET)
Type:
    Library Function
Purpose:
    Compute the classical matching cumulative distribution function.
Description:
    The classical matching distribution has the following probability mass function:

      p(x;k) = (1/x!)*SUM[i=1 to k-x][(-1)^i/i!]    x = 0, 1, 2, ..., k

    with k a non-negative integer denoting the number of items parameter.

    The cumulative distribution function is computed by summing the probability density function.

Syntax:
    LET <y> = MATCDF(<x>,<k>)             <SUBSET/EXCEPT/FOR qualification>
    where <x> is a variable, a number, or a parameter containing values between 0 and <k>;
                <k> is a number or parameter that defines the upper limit of the matching distribution;
                <y> is a variable or a parameter (depending on what <x> is) where the computed cdf value is stored;
    and where the <SUBSET/EXCEPT/FOR qualification> is optional.
Examples:
    LET A = MATCDF(3,20)
    LET Y = MATCDF(X,100)
Note:
    For sufficiently large values of k, the classical matching distribution can be accurately approximated with a Poisson distribution with lambda = 1. Dataplot computes MATCDF from the above definition for values of k < 20. For values of k ≥ 20, Dataplot computes MATCDF using the Poisson cdf with lambda = 1.
Default:
    None
Synonyms:
    None
Related Commands:
    MATPDF = Compute the matching probability mass function.
    MATPPF = Compute the matching percent point function.
    POIPDF = Compute the Poisson probability mass function.
    LCTPDF = Compute the leads in coin tossing probability mass function.
    DISPDF = Compute the discrete uniform probability mass function.
    LOSPDF = Compute the lost games probability mass function.
    ARSPDF = Compute the arcsine probability density function.
    BETPDF = Compute the beta probability density function.
    UNIPDF = Compute the uniform probability mass function.
Reference:
    Johnson, Kotz, and Kemp (1992), "Univariate Discrete Distributions", Second Edition, Wiley, pp. 409-410.
Feller (1957), "Introduction to Probability Theory", Third Edition, John Wiley and Sons, pp. 107-109. Applications:
    Distributional Modeling
Implementation Date:
    2006/6
Program:
     
    TITLE CASE ASIS
    TITLE Matching Cumulative Distribution Function CR() ...
          (N = 50)
    LABEL CASE ASIS
    Y1LABEL Probability
    X1LABEL X
    LINE BLANK
    SPIKE ON
    TIC OFFSET UNITS SCREEN
    TIC OFFSET 3 3
    PLOT MATCDF(X,50) FOR X = 0 1 50
        
    plot generated by sample program

Date created: 6/20/2006
Last updated: 6/20/2006
Please email comments on this WWW page to alan.heckert@nist.gov.